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Full Vehicle NVH
Access the Assemble, Analyze, NVH Tools, NVH Post, and Physics AI ribbons.
Post-processing and Diagnostics
Define radiation conditions and create emissivity models.
Integrated Diagnostics
Calculate a response, perform contribution analysis, plot results, and perform diagnostic studies and study response changes.
Integrated Diagnostics - Load Processing
Load the sensitivity and force results from an OptiStruct *.pch or Nastran *.pch file to calculate the vehicle responses.

Welcome
What's New
View new features for HyperMesh NVH 2025.1.
Get Started
Learn the basics and discover the workspace.
Tutorials
Discover NVH functionality with interactive tutorials.
Full Vehicle NVH
Access the Assemble, Analyze, NVH Tools, NVH Post, and Physics AI ribbons.
- Assembly
  Learn how to create, open, import and save models.
- Analysis
  Set up the simulation model, materials, domains and boundaries.
- NVH Tools
- Prepare Module
  Create, organize and manage the CAE parts.
- Post-processing and Diagnostics
  Define radiation conditions and create emissivity models.
  - Load an NVH Utility
  - Integrated Diagnostics
    Calculate a response, perform contribution analysis, plot results, and perform diagnostic studies and study response changes.
    - Integrated Diagnostics - Load Processing
      Load the sensitivity and force results from an OptiStruct *.pch or Nastran *.pch file to calculate the vehicle responses.
    - Integrated Diagnostics - Vehicle Response
      Calculate and plot responses specific to loadcases, including general loadcases, power train input, and road profile input from an OptiStruct or Nastran Punch file.
    - Integrated Diagnostics - Contributions Tab
      Perform contribution analysis for the vehicle response between sensitivity and forces, with the respective files loaded in the Loadcase Processing tab, the vehicle response calculated or loaded, and the loadcases selected in the Vehicle Response tab, Powertrain input, or Road Profile input.
    - Integrated Diagnostics - Diagnostics
      After plotting the response(s), assign diagnostic results by invoking the Diagnostic Results dialog.
    - Integrated Diagnostics - Study
      Perform a Partial sum response study by excluding the contributions from the selected contributors. The list of contributors available depends on the diagnostics done before arriving at the Study tab.
  - Modal Participation
    Plot modal/panel participation curves from an OptiStruct .h3d file or an MSC Nastran .f06/.pch file.
  - Grid Participation
    The Grid Participation utility allows you to plot panel grid participation results and then use advanced scaling contour capabilities to isolate key contributing areas.
  - Energy Distribution
    Visualize the distribution of energy within a full vehicle NVH model, as a way to understand what components are dominating the vehicle response.
  - Transfer Path Analysis
    Identifies the complex contribution of the excited structure through attachment points to a response in the responding structure.
  - Design Sensitivity Analysis
    Design sensitivity represents a change in response with respect to a change in a design variable, which is typically used for optimization.
  - Order Analysis
    Generates and post-processes engine order related data from an OptiStruct or Nastran frequency response analysis that contains either RPM-based loading subcases or order-based loading subcases.
  - Modal FRF
    Calculate a frequency response based on modal results.
  - Model Correlation
    The Model Correlation utility determines the degree of similarity or correlation between two sets of results.
  - Radiated Sound
    The Equivalent Radiated Sound utility post-processes the results of exterior structure-borne radiated sound.
  - Global Modes
    Identifies global modes from an OptiStruct or Nastran modal analysis.
  - Flow Induced Noise/General Signal Processing
    The General Signal Processing utility processes the time domain pressure results from CFD simulations and visualizes the results in both the time and frequency domain.
  - Green House Noise
    Post-process the pressure result of a vehicle panel obtained from ultraFluidX.
  - Mount Optimization
    Predicts powertrain rigid body mode frequencies and kinetic energy distribution, which play a critical role in optimizing the mount stiffness and layout configuration, by decoupling powertrain rigid body modes and reducing vibration transmission.
  - Optimization, RBDO
    Optimizes sensitive parameters for multiple sample analysis results using the RBDO or Deterministic approach.
  - Multiple Sample Analysis
    Post-process results from a Multiple Sample Analysis, including plotting a spread of responses (+/-95% and mean).
  - Deterministic Optimization
    Reads results from an OptiStruct optimization run and processes the results to review the overlay of the NVH responses, baseline versus optimized. Compare changes in the design variable values, baseline versus optimized.
  - Display Options
    Customize plots using the following options
  - Filter Contributors
    Filters contributors to a smaller set of data.
High Frequency NVH
High frequency NVH is an implementation of Statistical Energy Analysis (SEA), and is used to predict and analyze the vibration and acoustic response of complex dynamic systems.
Squeak and Rattle
Create and evaluate evaluation lines and optimize interfaces to eliminate squeak and rattle issues.

View All Altair HyperWorks Help

Integrated Diagnostics - Load Processing

Load the sensitivity and force results from an OptiStruct *.pch or Nastran *.pch file to calculate the vehicle responses.

File selection

Select the following file types:

Transfer Function: Select an OptiStruct or Nastran *.pch file, where the Transfer Function output is available.
Force: Select an OptiStruct or Nastran *.pch file where the Force output is available, then click Load.
Calculate and Export Forces: Calculates the vehicle response using the loaded transfer and forces files and exports the data into a PCH file. This PCH file gets loaded in the vehicle response tab.

TF tab

Review the TF options from this tab.

Subcase ID: Select a transfer function subcase from the drop-down menu.
TF Type: Select the transfer function type depending on the response type, pressure, velocity, acceleration.
Response ID: Select the grid ID of the response from the drop-down menu.
Component: Select the component of response grid ID from the drop-down menu.
Display Options: Customize the response plot, including scale, weighting, and the plot layout.
View TF: Once the result selection options are complete, select View TF to display the TF data.

Force tab

Review the forces from this tab.

Subcase ID: Select a transfer function subcase from the drop-down menu.
Subcase Label: Enter the subcase label.
Grid ID: Select the grid ID of the force output from the drop-down menu.
Component: Select the component of force grid ID from the drop-down menu.
Display Options: Customize the response plot, including scale, weighting, and the plot layout.
View Force: Once the result selection options are complete, select View TF to display the TF data.

Coherence On/Off Parameters

Coherence Threshold Frequency: Specify the threshold frequency for coherence.
Wheelbase: The wheelbase to be used for the calculation; the value is taken from the result file.
Vehicle Speed: The vehicle speed to be used for the calculation; the value is taken from the result file.